- Clinical science
Connective tissue is an important biological tissue composed of an extracellular matrix that binds, anchors, and supports organs. There are various types of connective tissue, all of which consist of varying combinations of fibers, cells, and intercellular substance. Over 200 conditions, which may be inherited or autoimmune, affect connective tissue, and they are collectively known as connective tissue diseases (CTDs). Inherited CTDs are caused by mutations that affect one of the two fibers (collagen and fibrin). Autoimmune CTDs have no clear etiology, but the incidence is higher in women and among genetically predisposed individuals. As the name suggests, in autoimmune CTDs, the immune system develops antibodies against components of connective tissue. Individual conditions can affect a vast range of bodily structures (including cartilage, blood vessels, bone, tendons, and organs) and thus present with a wide array of clinical findings.
- Loeys-Dietz syndrome 
Clinical features vary greatly among individual diseases. The table below provides a general overview of the more common features.
|Autoimmune CTDs||Inherited CTDs|
|General features|| || |
|Musculoskeletal symptoms|| |
|Skin manifestations|| |
This table lists the most important connective tissue disorders and some examples of their clinical features. For more information on Marfan syndrome, Ehlers-Danlos syndrome, and osteogenesis imperfecta, see the respective learning cards.
|Condition||Etiology||Pathophysiology||Clinical features (examples)|